Simrad AP27 Manual page 123

Display readout
Failure active
Control Unit
ACXX current
overload
Low 15 volt
Bypass/clutch
overload
Bypass/clutch
disengaged
ACXX high
temp.
Memory failure
ACXX
20221586B
Probable fault
Active control unit
goes silent.
The drive unit shut
down due to an
excessive load or a
short circuit.
Internal 15 Volt
supply in Autopilot
Computer below
limit.
Clutch/bypass
current exceeds 2,5
Amps (overload or
short circuit).
Poor connection or
open circuit in
bypass/clutch coil
Excessive
temperature in
Autopilot
Computer (>75°C),
possible long term
overload.
Wrong checksum
on memory
parameters or
variables.
Autopilot
Computer will use
default values.
Recommended action
1. Press the STBY button on an
"Inactive" unit to reset.
2. Check/repair Robnet2 cable.
3. Replace the control unit PCB.
1. Check the drive unit and drive unit
installation/Manual steering/
Rudder.
2. Disconnect the drive unit. If the
fault is still present, replace the
Autopilot Computer Power PCB.
1. Replace Autopilot Computer Main
PCB
2. Replace Autopilot Computer
Power PCB if Mains voltage is
12V.
1. Check actual current
2. Check voltage marking on coil
3. Check coil resistance (through
connecting wires)
1. Check connections
2. Replace bypass/clutch if open.
3. Perform new "Rudder test".
1. Switch off autopilot
2. Check for backload in Drive
unit/steering system.
3. Check that the autopilot computer
specifications matches Drive unit.
Perform a "Master reset" and make a
new "Dockside set-up". Switch off
and on again. If the alarm is repeated,
replace Autopilot Computer Main
PCB.
Trouble shooting
121